Teen Marijuana Use is Down Significantly in Colorado’s Legal Era

Teen marijuana use fell sharply in Colorado in the years 2014 and 2015, after the opening of that state’s recreational marijuana market, new federal survey data show.

The state-level data from the National Survey on Drug Use and Health showed that 18.35 percent of Coloradans ages 12 to 17 had used marijuana in the past year in 2014 or 2015, down from 20.81 percent in 2013/2014. (In this survey, years are paired for state-level data to provide larger sample sizes). That works out to roughly a 12 percent drop in marijuana use, year-over-year.

Year-over-year teen marijuana use fell in most states during that time period, including in Washington, the other state to open recreational marijuana markets in 2014. But that drop wasn’t statistically significant.

Conversely, adult marijuana use rose significantly in Colorado over the same time period. Among Coloradans ages 26 and older, past-year marijuana use rose from 16.80 percent in 2013/2014 to 19.91 percent in 2014/2015. Annual adult marijuana use was up in most statesduring the same time frame. The legal marijuana markets in Colorado, Washington and elsewhere feature strict age and purchasing limits.

This federal data released this week is the first clear evidence of a drop in teen marijuana use in Colorado following legalization. Legalization supporters have long argued that the best way to prevent underage marijuana use is to legalize and regulate the drug.